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81.
T. Yu. Samgina V. A. Gorshkov E. A. Vorontsov V. V. Bagrov I. E. Nifant’ev A. T. Lebedev 《Journal of Analytical Chemistry》2010,65(13):1320-1327
Mass spectrometric de novo sequencing of skin secretion peptides from genus Rana is complicated because of C-terminal disulfide cycles present in their structure. Brevinin-1E and brevinin-2Ec from the skin
secretion of the Marsh Frog R. ridibunda were used for a comparative study of six N-phenylmaleimide derivatives as new alkylating agents for cysteine thiol moieties.
The paper describes the synthesis and confirmation of the structures of the obtained compounds. A procedure was developed
for modifying thiol groups with the proposed reagents. Alkylation efficiency and the effect on the peak intensity in matrix-assisted
laser desorption/ionization (MALDI) spectra were investigated. The best results were obtained for 2,4- and 2,5-dimethylphenylmaleimides.
Additionally tested iodoacetic acid was shown to be a powerful modifier of thiol groups, while its excess notably increases
the intensities of the peaks of protonated molecules in the MALDI mass spectra of both peptides. 相似文献
82.
A. V. Gorshkov 《Journal of Mathematical Sciences》2010,167(3):340-357
We consider the model of atmosphere dynamics and prove the uniqueness of a solution in a bounded domain
W ì \mathbbR3 \Omega \subset {\mathbb{R}^3} in the space V(Q) of weak solutions equipped with the finite norm
|| f ||V(Q)2 = \textvrai supt ? [ 0,T ] || f ||L2( W)2 + || ?3f ||L2(Q)2. \left\| f \right\|_{V(Q)}^2 = \mathop {{\text{vrai}}\,{ \sup }}\limits_{t \in \left[ {0,T} \right]} \left\| f \right\|_{{L_2}\left( \Omega \right)}^2 + \left\| {{\nabla_3}f} \right\|_{{L_2}(Q)}^2. 相似文献
83.
A. V. Gorshkov 《Computational Mathematics and Mathematical Physics》2018,58(1):90-101
Stable nonlocal invariant manifolds for the Burgers equation defined on R+ are constructed. One problem of a boundary control stabilizing the solution of this equation to zero is also studied. Results of numerical experiments are presented. 相似文献
84.
It is shown that condensation of water vapor produces dynamic instability of atmospheric air and induces air circulation that is characterized by observable air velocities and persists independently of the magnitude of horizontal temperature gradients. 相似文献
85.
V. A. Ivanov O. T. Gavlina E. A. Ilyukhina V. I. Gorshkov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2007,81(11):1723-1727
The influence of temperature on the exchange of calcium and sodium ions from solutions of 2.3–2.8 g-equiv/l concentrations on KB-2e4 gel polyacrylic cationite, KB-4P2 and KB-4 gel polymethacrylic cationites, and Purolite C104 polyacrylic cationite was studied over the temperature range 273–400 K. It was shown that, simultaneously with a substantial increase in selectivity with respect to calcium ions, the differential enthalpy of the ion exchange reaction increased linearly on all polyacrylic and polymethacrylic cationites as the temperature grew. 相似文献
86.
Ts. Zhapova L. D. Modonova N. N. Pogodaeva A. L. Vereshchagin A. G. Gorshkov S. V. Zinchenko A. A. Semenov 《Chemistry of Natural Compounds》1992,28(5):421-429
Two known flavonoids, the 7-O-α-L-rhamnopyranosides of kaempferol and of quercetin, and also the new acylated glycoside quercetin 3-O-[O-(6-caffeoyl-β-D-glucopyranosyl)-(1→2)-β-D-glucopyranoside 7-O-α-L-rhamnopyranoside (czekanoside A) have been isolated from the epigeal part ofAconitum baicalense Turcz, ex Rapaics (A. Czekanovskyi Steinb.). Their structures have been demonstrated by the methods of IR, UV,1H, and13C NMR spectroscopies and FAB mass spectrometry and also with the aid of acid hydrolysis. 相似文献
87.
Qinyuan Wu Gordon A. Anderson Harold R. Udseth Michael G. Sherman Steven Van Orden Ruidan Chen Steven A. Hofstadler Michael V. Gorshkov Dale W. Mitchell Alan L. Rockwood Richard D. Smith 《Journal of the American Society for Mass Spectrometry》1996,7(9):915-922
A new in-magnetic field electrospray ionization (ESI) and Fourier transform ion cyclotron resonance mass spectrometer has been constructed and evaluated. This system is characterized by the use of multiple concentric cryopanels to achieve ultrahigh vacuum in the ion cyclotron resonance cell region, a probe-mounted internal ESI source, and a novel in-field shutter. Initial experiments demonstrate high resolution mass measurement capability at a field strength of 1 T. Mass resolution of 700,000 has been obtained for the 3+ charge state of Met-Lys-bradykinin (at m/z 440) generated by electrospray ionization. When electron impact ionization was employed, resolution in excess of 9,200,000 was achieved for nitrogen molecular ions (N 2 + ). Isotopic resolution for molecular ions of bovine ubiquitin (MW=8565 µ) also was achieved by using small ion populations. 相似文献
88.
O. N. Malyshev A. V. Belozerov M. L. Chelnokov V. I. Chepigin V. A. Gorshkov A. P. Kabachenko A. G. Popeko J. Rohach R. N. Sagaidak A. V. Yeremin S. I. Mulgin S. V. Zhdanov 《The European Physical Journal A - Hadrons and Nuclei》2000,8(3):295-297
The new neutron deficient isotope 217U was produced in the bombardment of the 182W target with 40Ar ions and identified using a recoil-- correlation method. The -decay energy and the half-life of 217U were determined to be 8005 ± 20 keV and 15.6 +21.3
-5.7 ms, respectively.
Received: 18 May 2000 / Accepted: 21 June 2000 相似文献
89.
V.R. Galakhov M.A. Korotin N.A. Ovechkina E.Z. Kurmaev V.S. Gorshkov D.G. Kellerman S. Bartkowski M. Neumann 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,14(2):281-286
The electronic structure of LiMnO2 and Li2MnO3 was studied by means of X-ray photoelectron and soft X-ray emission spectroscopy. For LiMnO2, LSDA and LSDA+U calculations were carried out. The LSDA+U calculations are in rather good agreement with the measured valence-band structure as well as with the magnetic and electrical
properties of LiMnO2. It is shown that the band gap in LiMnO2 is determined by the charge-transfer effect.
Received 15 March 1999 and Received in final form 14 July 1999 相似文献
90.
Mikhail E. Belov Michael V. Gorshkov Harold R. Udseth Richard D. Smith 《Journal of the American Society for Mass Spectrometry》2001,12(12):4840-1319
Undesired fragmentation of electrospray generated ions in an rf multipole traps can be problematic in many applications. Of special interest here is ion dissociation in a 2-D quadrupole ion trap external to a Fourier transform ion cyclotron resonance mass spectrometer (FTICR MS) used in proteomic studies. In this work, we identified the experimental parameters that determine the efficiency of ion fragmentation. We have found that under the pressure conditions used in this study there is a specific combination of the radial and axial potential well depths that determines the fragmentation threshold. This combination of rf and dc fields appears to be universal for ions of different mass-to-charge ratios, molecular weights, and charge states. Such universality allows the fragmentation efficiency of the trapped ions in the course of capillary liquid chromatography (LC) separation studied to be controlled and can increase the useful duty cycle and dynamic range of a FTICR mass spectrometer equipped with an external rf only 2-D quadrupole ion trap. 相似文献
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